Cargo items have long been transported as containerized freight inside rectangular closed boxes, one example of which measures roughly 8 feet wide, 8 feet high, and 20 to 50 feet long. Fully loaded, these containers are often very heavy, approaching 20 tons.
Recently, users have begun to use these containers primarily for storage of residential and commercial materials rather than merely for shipment. For example, a container may be delivered by a storage company to a residence, where the users may load the material into the container at their convenience. Later, the storage company accepts the container and delivers it to a long-term storage facility. Because these types of users are not associated with the freight industry, their facilities often have landscaping, driveways, sidewalks, and other loading zones that are not capable of withstanding abuse. A traditional loading and transport vehicle, often called a hook truck, will attach a lift mechanism to the container and lift one end of the container, pull the container up and forward, dragging the other end of the container along the ground, driveway, or roadway, until the container is fully loaded onto the hook truck. Loading the container in this way damages the supporting surface when that surface is not specially prepared for handling freight.
Alternatively, it is common to use a forklift or similar independent lift device to load a container onto a vehicle. A difficulty encountered by using a forklift is that a forklift requires a great deal of room to maneuver beside the container and vehicle during loading and unloading.
A third way of loading a container onto the truck uses a jack arrangement to lift the four corners of the container, so that the truck can be driven underneath it; or alternatively, the jacks have wheels so that the container can be rolled onto the truck. A difficulty encountered using this method is that it requires manual labor and considerable assembly and disassembly time to set up the jacks.
Containers are often loaded onto trailers for transport with a semi-articulated tractor-trailer combination. Typically, containers are loaded onto the trailer from the side using a forklift, or from above using an overhead crane to lift the container from its storage location, swing the container directly over the trailer and then set the container onto the trailer. A forklift takes a considerable amount of maneuvering space. An overhead crane requires expensive capital investment. Either a crane or a forklift takes a large space to operate. In addition, both methods require a place to store the forklift or crane when not in use, as neither can be used to transport the container any appreciable distance. A separate forklift or crane must be provided to unload the vehicle once it arrives at its destination.
Thus, the invention provides a way to load a container onto a transport vehicle without damaging the surface on which the container rests and while using a minimal amount of space and a minimum of capital investment. The invention also provides for a container transport vehicle with an integral loading mechanism so that it may be used to load the container at the departure point and unload it at the destination.
Additional advantages and novel features of the invention will be set forth in part in the following description and will become apparent to those skilled in the art upon examination of the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.